at this stage i would recommend blocking in colour; it'll help with grouping details and getting proportions right; you can drag your concept in as a texture, apply it to a plane, then colour sample the texture (shortcut c) and go from subtool to subtool, rbg > fill
Sounds to me like you're looking for this: This will align to X, Y, Z anything you have selected. Combine it with constrain to get more control as well.